binman: Select compression bintools in cbfs_util class

Select the lz4 and lzma_alone bintools in cbfs_util class to centralize
the supported compression algorithm evaluation inside the class and over
multiple classes.

Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
Reviewed-by: Simon Glass <sjg@chromium.org>